They are a carbon fiber tub, like an F1 car. I am not a big fan of Enzos, I personally think the last "real" Ferrari was the F40, BUT I do have to say that the Enzo looks like a good car to be in if you plan to crash at 200 mph.
Now, as far as idiots and Enzos are concerned, please refer to the Enzo crash in Malibu with Eriksson, the guy on the run for embezzling millions from his "company". Car clipped a concrete light pole at 150+ MPH, cuts the car in two, and the guy walked away. Not bad! See, the car is as safe for the bad guys as it is for the good guys.
Colin